Dan Hodges is a former Labour Party and GMB trade union official, and has managed numerous independent political campaigns. He writes about Labour with tribal loyalty and without reservation. You can read Dan's recent work here

Newark could end Ukip's momentum: it's a headache Nigel Farage could have done without

Yesterday evening, as the news emerged that Patrick Mercer had decided to fall on his consultancies, the feeling around Westminster was Christmas had come early for Ukip. Downing Street was facing a “nightmare scenario”, while Nigel Farage had been handed a “by-election gift”.

But this morning Britain is waking up to another misty April dawn. Christmas hasn’t arrived quite as quickly as some people were hoping.

One reason is a realisation of the scale of the challenge facing Ukip in Mercer’s hastily vacated Newark seat. In 2010 the party came 26,000 votes behind the Tories. Not necessarily an insurmountable hurdle given the vagaries of parliamentary by-elections. But by no means the nailed on certainty some supporters – and panicky Tory MPs – were claiming last night.

This in turn presents a dilemma for Ukip Godhead Nigel Farage. Even before Mercer made his announcement the consensus was the Chosen One’s moment had arrived. This was the opportunity to shatter the cozy Westminster consensus once and all.

In reality, however, it seems far from certain the Chosen One is planning to choose Newark. “A reservation in my mind is I haven't particularly got connections with the local area”, he claimed last night. Which is code for, “I’m scared I might lose”. As well as being code for “and even if I win, I’m going to lose the seat in 12 months time. Unless I join the chicken run. And I’m not supposed to be that sort of politician”.

And then there is the issue of what this by-election means Ukip’s political “momentum”. With the possible exception of “one nation” momentum is the most overused phrase in British politics. The idea that because voters have done one thing one week they’re duty bound to do the same thing in larger numbers in a year’s time, is bonkers.

But Ukip are putting big store on generating some “big mo” in the wake of the European elections. And a failed by-election campaign – especially one centred on their leader – would bring their mo to a shuddering halt.

So as we peer through the midmorning mist, this is the political reality. If Farage runs there’s a chance he may win, but an equally good chance he may lose. If he doesn’t run he’ll be accused of bottling it. Rightly, because he will have done. And the nailed-on success of a good Ukip showing in the Euro elections is now being overshadowed by the uncertainty of an electoral coin toss in Newark.

Christmas come early? In reality, Newark is a headache both the Tories and Ukip could have done without.